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1.
Fossil species ofMelanopsis from a freshwater formation in the Jordan Valley (near Al-Qarn) were investigated and the deposits containing these species
are formally described as Al-Qarn Formation. Four species were found:Melanopsis buccinoidea
Olivier,M. tchernovi
Heller & Sivan,M. costata
Olivier andM. aaronsohni
Blanckenhorn.Melanopsis costata was represented by two groups, “stepped” and “non-stepped”, the latter differing in its lower figurativity index. Intermediates
were found betweenM. buccinoidea andM. tchernovi; they may be hybrids. TheMelanopsis assemblage bridges the faunal gap, in the Jordan Valley, between the 2 Ma lake of ‘Erq el Ahmar on the one hand and the 0.8–1.7
Ma lake of ‘Ubeidiya on the other. This suggests an early Pleistocene age of about 1.8 million years for the Al-Qarn Formation. 相似文献
2.
Jing Zhang Yan Liu Dan Yu Hongze Song Jingjin Cui Tao Liu 《Journal of applied phycology》2011,23(2):165-171
Hybridization of gametophytes, continuous self-crossing and targeted selection were utilized to breed a new Laminaria variety. After five-generation selection breeding, the new variety “Rongfu” was obtained. Its male parent “Yuanza No.10”
was the high-yield cultivation variety, and its female parent was variety “Fujian” which could tolerate relatively high seawater
temperature. “Yuanza No.10” and “Fujian” were different but complement in their morphological characteristics and biological
habits. Variety “Rongfu” was bred through their hybridization which exhibited high-yield potential and high seawater temperature
tolerance. The results of traits evaluation in consecutive years showed that “Rongfu” attained higher yields by 24–27% compared
to the control (widely used commercial variety) and also contained considerable amounts of iodine, mannitol, and algin. When
seawater temperature was 18–21°C, the blade growth of “Rongfu” was maintained and tissue loss by abrasion was significantly
lower than the control. Since the adoption of variety “Rongfu” in 2001, its cultivation areas have been extended to Shandong,
Fujian and Guangdong province and have reached 14,133 ha currently, i.e., almost one-tenth of the total cultivation areas
of Laminaria in China. The results of Random Amplified Polymorphic DNA analysis showed that the relationship between “Rongfu” and other
cultivation varieties in China was very close. 相似文献
3.
A reevaluation of floral and vegetative morphology together with data from analysis of floral fragrance and flavonoid co-pigment
chemistry suggest that specific status is warranted for the two kinds ofPhalaenopsis violacea Witte known informally as the “Bornean type” and the “Malayan type.”Phalaenopsis violacea var.bellina Rchb.f. is elevated to specific rank, providing a name for the “Bornean type” plants. 相似文献
4.
Patrick J. Brennan 《Journal of biosciences》1984,6(5):685-689
There is now a considerable body of evidence to suggest that the phthiocerol-containing lipids, including the phenolic glycolipids,
comprise the so-called “peribacillary substance”, “spherical droplets”, “foamy structures” and “capsular materials” ofMycobacterium leprae. Thus, the phthiocerol-containing lipid capsule may be directly responsible for the intracellular survival ofMycobacterium leprae. 相似文献
5.
Yuzuru Hamada 《Primates; journal of primatology》1984,25(4):485-506
A method based on the Fourier analysis is proposed, which describes and analyzes the contour morphology of carpal bones by
separating morphology into factors of shape and size. Here, “size” refers to the average diameter of the contour. The “shape”
is expressed byshape factors which are derived from the Fourier series and the “shape” of a monkey is expressed by ashape index which is calculated fromshape factors. The age change in the morphology of the lunate and capitate ofMacaca fuscata fuscata was analyzed by this method. The development of “shape” approximately completes by 3 years of age, whereas increase in “size”
begins its spurt at that age as do body weight and anterior trunk length. By applying this method to other macaque species,
it was found thatM. mulatta, M. f. yakui andM. cyclopis exhibit similar patterns of growth and development of carpal bones to those ofM. f. fuscata. Patterns found inM. fascicularis differ in that its bones develop faster than in the other macaques with respect to the “shape,” but remain small with respect
to the “size.” 相似文献
6.
George D. Koufos Louis de Bonis Dimitris S. Kostopoulos Laurent Viriot Theodora D. Vlachou 《Pal?ontologische Zeitschrift》2004,78(1):213-228
Two skulls, two mandibles and some postcranials ofMesopithecus from the locality “Vathylakkos 2” of Axios Valley (Macedonia, Greece) enlarge our knowledge about the genus and its differentiation.
The new material together with an old skull from the same locality is compared with the Pikermi, “Ravin des Zouaves 5” (Axios
Valley), and Maramena (Serres basin) samples. It is concluded that the VathylakkosMesopithecus resemblesM. pentelicus from Pikermi, as wellM. delsoni from “Ravin des Zouaves 5” and it is referred asMesopithecus sp. aff.M. pentelicus. The biochronological age of “Vathylakkos 2” has been considered as MN 12, while recent magnetostratigraphic data indicate
an age of about 7.5 Ma. This age confirms the position of the VathylakkosMesopithecus between Pikermi and “Ravin des Zouaves 5”. Some dental indices compared with those of the RecentCercopithecus suggest that the Vathylakkos sample is monospecific.
相似文献
7.
Specimens of eelpouts were found in the northern Sea of Japan that were externally similar to Lycodes yamatoi Toyoshima, 1985, but their coloration differed from the coloring known for this species. Comparative analysis of meristic
characters and sequence comparison of mtDNA COI and cytb gene fragments did not reveal distinctions between specimens with
different types of coloration. All studied specimens belong to L. yamatoi. The live color pattern of L. yamatoi is characterized by high variation, with two main types of coloration, “dark” and “bright.” 相似文献
8.
Summary The “problematic microfossil”Probolocuspis espahkensis, described as, “incertae sedis” by Br?nnimann, Zaninetti, Moshtaghian and Huber (1974) from the Carnian Espahk Formation
near the small village of Espahk (Tabas area, NE Iran) represents a dasycladacean alga attributed preliminary to the Family
Acetabulariaceae, Tribe Clypeineae. The holotype ofProbolocuspis espahkensis, designated by Br?nnimann et al. (1974), is only a part of the alga.
Contribution to the Triassic Paleontology of Iran No. 8; for No. 7: see Senowbari-Daryan, B. (2002); Jb. Geol. Bundesanst.,
143/I, Wien 相似文献
9.
Rocket line immunoelectrophoresis was used to study the taxonomy ofAzotobacter andAzomonas assessed by reaction with antiserum to the AVO2 strain ofAzotobacter. Forty-five cultures, comprising seventeen species in five genera, showed that antigen “β”, like high-titer somatic agglutination,
was restricted to all 11 strains ofAzotobacter vinelandii and to one strain which has been namedAzotobacter macrocytogenes (10EM). A thermoresistant antigen (“γ”) was found to be shared by all strains and species ofAzotobacter andAzomonas investigated. 相似文献
10.
D. E. Tyler 《Human Evolution》2003,18(3-4):229-241
There are now eleven known mandibular remains from the Lower and Middle Pleistocene of Java, all but one being from the Sangiran
site. All of these have been assigned toHomo erectus by most workers, while others have suggested as many as four different hominoid taxa. The author finds that the jaws cannot
be a homogeneous sample. Morphologically, they are a mixture of undoubtedH. erectus, “H. meganthropus,” and possibly a pongid. If the jaws are allH. erectus then they have a sexual dimorphism exceeding that of modern gorillas. The case of“Pithecanthropus dubius” (Sangiran 5) is even less certain; even its hominid status is disputed. If it is indeedHomo it must be placed with the other“H. meganthropus” specimens. Its size and morphology are well beyond the known range anyH. erectus. 相似文献
11.
The Role of Organic Acids in the Domestication of
Oxalis tuberosa: A New Model for Studying Domestication Resulting in Opposing Crop Phenotypes. Though few crops display directly opposing domesticated phenotypes, these crops may be the key to understanding domestication
processes that address conflicting selective pressures in the agricultural ecosystem. Two relatively well-known examples are
cassava (Manihot esculenta Crantz), which has high-cyanide and low-cyanide varieties, and potato (Solanum section Petota). Among the potatoes are several species, including the common potato (Solanum tuberosum L.), that have low levels of glycoalkaloids and there are other species of “bitter potato” with elevated levels of glycoalkaloids.
We propose that Oxalis tuberosa Molina, “oca,” may represent a third example of such a crop system, with opposing high organic acid and low organic acid
cultivars. Each cultivar set has different cultural food preparation practices (“use-categories”), similar to the “use-categories”
that have been described for potatoes in the Andes (Brush et al. Economic Botany 35;70–88, 1981; Zimmerer Journal of Biogeography 18;165–178, 1991). Our initial analyses suggest that organic acids in tubers may be an important biochemical difference between use-categories,
based on both oxalic acid and pH data. Here, we review our understanding of organic acids in oca tubers, while highlighting
areas that merit further investigation. 相似文献
12.
13.
Monoclonal antibodies (mAbs) W6/32, HC10, and 4E were used to precipitate class I antigens from 21 selected individuals with
at least oneHLA-C “blank” allele. In 19 of these individuals, characteristicHLA-C banding patterns which could be precipitated by all three HLA class I mAbs were observed on one-dimensional isoelectric focusing
gels-obviously the gene products ofHLA-C “blank”. At least four allelic HLA-C “blank” gene products with different isoelectric points could be discerned. All of them
segregated withHLA-C “blank” haplotypes in informative families; two of them were associated withHLA-B51, one withHLA-B38, and one withHLA-B18. Reactivity of the HLA-C “blank” heavy chains with mAb W6/32 indicates that they are able to associated with beta-2 microglobulin,
and hence are most probably expressed at the cell surface. 相似文献
14.
A method for estimating the complexity of behavioral patterns of ants based on the Kolmogorov complexity is considered. Behavioral
sequences are presented as “texts” compressed with the KGB Archiver (v. 1.2). The elements of behavior (a total of 10) singled
out from video records served as an alphabet. The comparison of “successful” and “incomplete” hunting behaviors in Myrmica rubra showed that successful hunting patterns were characterized by less complexity than “incomplete” ones. It was assumed that
complete patterns had less redundancy and better predictability. The smallest complexity was revealed in complete hunting
patterns of naive (laboratory reared) ants in comparison with members of a natural colony. In perspective, quantitative evaluation
of complexity of behavioral patterns will help to evaluate the level of discrete variability within ant colonies. 相似文献
15.
The fundatrix ofCeratovacuna nekoashi attacks an axillary bud ofStyrax japonica to form a “cat's-paw” gall with a number of completely closed subgalls. Larvae produced early by the fundatrix enter subgalls,
but late-produced ones cannot because the subgalls close too early. The average number of these “outsiders” produced per gall
was 3.81±2.37 (n=26). In spite of their small numbers, outsiders attacked caterpillars placed on the gall. Thus outsiders
function to defend their gall against external attacks such as those from lepidopterous predators. 相似文献
16.
The plasma membrane H+-ATPase activity was determined under various growth conditions using the yeastsSaccharomyces cerevisiae andSchizosaccharomyces pombe. Under early batch-growth conditions in a rich medium, the budding yeastS. cerevisiae ATPase specific activity increased 2-to 3-fold during exponential growth. During late exponential growth, a peak of ATPase
activity, followed by a sudden decrease, was observed and termed “growth-arrest control”. The growth arrest phenomenon ofS. cerevisiae could not be related to the acidification of the culture medium or to glucose exhaustion in the medium or to variation of
glucose activation of the H+-ATPase. Addition of ammonium to a proline minimum medium also stimulated transiently the ATPase activity ofS. cerevisiae. Specific activity of the fission yeastS. pombe ATPase did not show a similar profile and steadily increased to reach a plateau in stationary growth. Under synchronous mitotic
growth conditions, the ATPase activity ofS. cerevisiae increased during the cell division cycle according to the “peak” type cycle, while that ofS. pombe was of the “step” type. 相似文献
17.
Lotfi Rabaoui Randa Mejri Sabiha Tlig-Zouari Lilia Bahri Oum Kalthoum Ben Hassine Costas S. Tsigenopoulos 《Hydrobiologia》2011,678(1):99-111
The Mediterranean fan mussel Pinna nobilis is an endangered invertebrate due to overexploitation and habitat deterioration. In this species, two distinctive morphs,
the “combed” and “straight and wide” forms, have been recorded and it is not known whether this morphometric variability is
attributed to genetic or environmental factors. In this study, we used mitochondrial COI sequences to describe the genetic
variability of five Pinna nobilis populations sampled along the northern, eastern, and southern Tunisian coastline, and to examine whether there is a genetic
differentiation between the two forms of this species. DNA sequences of 675 bp from the mitochondrial COI gene have revealed
10 different haplotypes among 49 examined specimens. Haplotype diversity was high, ranging between 0.40441 and 0.80952, and
showed a decreasing North-East gradient, which seems to be explained by the hydrogeography of the study area. The mitochondrial
COI marker did not suggest a genetic distinctiveness between the two Pinna nobilis shell forms, “combed” and “straight and wide”. Although the morphometric plasticity of the fan mussel could be due to the
influence of environmental factors, further genetic studies using nuclear markers are envisaged to investigate whether this
differentiation is associated to gene flow restrictions. 相似文献
18.
Four strains of the phytopathogenic bacteriumCorynebacterium fascians (Tilford)Dowson were selected from our isolates and deposited in the Czechoslovak National Collection of Type Cultures (CNCTC) of the Institute
of Hygiene and Epidemiology in Prague. Two very virulent (Cor 83/82 “UPR” and Cor 82/81 “UP”) and one avirulent (Cor 81/80
“CP1b”) pelargonium strains, producing acid from rhamnose, were isolated from fasciations onPelargonium zonale W. One avirulent celery strain ofC. fascians (Cor 80/80 “CF4a”) was isolated from a root expiant ofApium graveolens L. growing on a nutrient mediumin vitro. Morphological, cultural, physiological and biochemical characteristics of these selected Czechoslovak isolates were compared
with the American patented strain cotype ATCC 12974. 相似文献
19.
A new almost complete specimen ofCoelurosauravus is reported from the Kupferschiefer (Upper Permian) at Mansfeld, Sachsen/Anhalt (Germany). The well preserved posterior half
of the skull differs from the previous finds by the large parietals and squamosals. The latter are interpreted as Single elements,
rather than as combination of squamosal and supratemporal, and it is supposed that they may have been partially mobile, features
of a male individual, and could be deployed in order to produce a threat display. Thin-sections of the patagial spars show
the typical anatomical structures of lamellar bones with rather sparsely distributed osteocyte lacunae. Compared to earlier
reconstructions a new restoration of the complete skeleton ofCoelurosauravus has a shorter trunk and “wings” with a delta-shaped outline and a feather-like “foresail”. What may be an impression of the
patagium is preserved on one specimen in association with the second spar. The presumed mechanism of unfolding and folding
the patagium is tried to be reconstructed. 相似文献
20.
Kenichi Ohara Momoko Hotta Daisuke Takahashi Takashi Asahida Hitoshi Ida Tetsuya Umino 《Ichthyological Research》2009,56(4):373-379
The genetic diversity and relationship among four morphotypes of Rhinogobius sp. OR, Gobiidae (“Tōshoku,” “Shinjiko,” “Gi-tōshoku,” and “Shimahire”) were investigated with seven microsatellite DNA loci,
and amphidromy of these morphotypes was verified by strontium (Sr) and calcium (Ca) deposition in the otolith. Samples of
“Tōshoku,” “Shinjiko,” “Gi-tōshoku,” and “Shimahire” were collected from, respectively, three, three, two, and four locations
in Japan. Microsatellite analysis detected high genetic diversity (based on the number of alleles, allelic richness, and average
observed heterozygosity) in the “Tōshoku” and “Shinjiko” morphotypes relative to the “Shimahire” morphotype; the “Gi-tōshoku”
morphotype had an intermediate level of variation. Almost all pairwise F
ST values were significantly different from zero (P < 0.001), except between two populations of “Tōshoku.” Clear genetic independence was observed between the “Shinjiko” and
“Shimahire” morphotypes in the Maruyama River. A principle component analysis based on microsatellite data indicated that
the “Tōshoku,” “Shinjiko,” and “Gi-tōshoku” morphotypes were genetically similar. Furthermore, the three populations of “Tōshoku”
were closely related each other, and two of those collected from the Lake Biwa system were a single population. There was,
however, a high degree of genetic differentiation between “Shimahire” and the other morphotypes; moreover, there was high
genetic divergence among four populations of the “Shimahire” morphotype. Amphidromous migratory histories were indicated by
Sr:Ca ratios in two of three populations of the “Shinjiko” morphotype and in one of two “Gi-tōshoku” morphotypes, whereas
all populations of the “Shimahire” morphotype were freshwater residents. The large genetic divergence and low genetic diversity
in “Shimahire” are likely related to migration history. 相似文献